Comparative Analysis of Catalytic Performance in Biodegradable Polymer Degradation Processes

Thesis Abstract

The accelerating accumulation of non-degradable plastics in the environment underscores the urgent need for sustainable waste management solutions, with biodegradable polymers emerging as a promising alternative due to their eco-friendly degradation profiles. However, the efficiency of polymer degradation is critically dependent on the catalytic processes involved, yet comparative assessments of catalytic performance across different catalysts remain limited. This study aims to evaluate and compare the catalytic efficacy of various catalysts—namely, titanium dioxide (TiO2), zinc oxide (ZnO), and manganese dioxide (MnO2)—in enhancing the biodegradation of polylactic acid (PLA), polyhydroxyalkanoates (PHA), and cellulose-based bioplastics under controlled laboratory conditions. The specific objectives include (1) to quantify and compare the degradation rates of selected biodegradable polymers catalyzed by TiO2, ZnO, and MnO2; (2) to analyze the morphological and chemical changes in polymers using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC); (3) to determine the influence of catalyst type and polymer composition on degradation efficiency through statistical modeling; and (4) to identify the most effective catalytic system for different polymer matrices to inform future biodegradable polymer design and waste management practices. Employing an experimental research design, the study utilizes a purposive sample of three biodegradable polymers—each with 30 specimens—treated with the three selected catalysts (total sample size 90 specimens). The polymers are subjected to accelerated degradation environments mimicking natural conditions, with degradation monitored over a 12-week period. Data collection involves gravimetric measurements, FTIR, SEM, and DSC to assess physical and chemical modifications, complemented by quantitative data on weight loss and molecular weight reduction. Data analysis employs analysis of variance (ANOVA) and multivariate regression models to compare degradation rates and identify significant factors influencing performance. The study applies the Theory of Catalytic Efficiency and the Principles of Polymer Chemistry to interpret the results within a robust theoretical framework. Expected findings include statistically significant differences in degradation rates among catalysts and polymer types, with TiO2 showing superior performance in PLA degradation, ZnO in PHA, and MnO2 excelling with cellulose-based bioplastics. The morphological and chemical analyses are anticipated to reveal catalyst-specific degradation pathways, such as surface erosion patterns and breakdown of functional groups. These insights are expected to contribute new knowledge on catalyst-polymer interactions, emphasizing the importance of tailored catalytic systems for different biopolymer matrices. Additionally, the study aims to develop a comprehensive model predicting degradation performance based on catalyst properties and polymer composition. The study’s contribution to knowledge lies in providing a systematic, comparative evaluation of catalytic performance in biodegradable polymer degradation, integrating empirical data with theoretical models, and offering practical recommendations for optimizing biodegradation processes. It bridges existing gaps by elucidating how specific catalysts influence degradation pathways across various biopolymer classes, thereby guiding the development of more efficient, environmentally sustainable biodegradable plastics. The main conclusion emphasizes the critical role of catalyst selection for targeted degradation purposes and proposes a framework for future research into catalytic systems tailored to diverse biodegradable polymers. Recommendations include further exploration of catalytic nanomaterials, scaling up of successful catalytic systems for industrial applications, and integration of findings into environmental policy and waste management strategies to enhance biodegradation efficiency in real-world settings.